content: /**
   * Copyright (c) 2016-present, RxJava Contributors.
   *
   * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in
   * compliance with the License. You may obtain a copy of the License at
   *
   * http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software distributed under the License is
   * distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See
   * the License for the specific language governing permissions and limitations under the License.
   */
  
  package io.reactivex.observable.internal.operators;
  
  import java.util.concurrent.atomic.AtomicInteger;
  
  import io.reactivex.common.*;
  import io.reactivex.common.disposables.CompositeDisposable;
  import io.reactivex.common.internal.functions.ObjectHelper;
  import io.reactivex.observable.*;
  
  public final class SingleEquals<T> extends Single<Boolean> {
  
      final SingleSource<? extends T> first;
      final SingleSource<? extends T> second;
  
      public SingleEquals(SingleSource<? extends T> first, SingleSource<? extends T> second) {
          this.first = first;
          this.second = second;
      }
  
      @Override
      protected void subscribeActual(final SingleObserver<? super Boolean> s) {
  
          final AtomicInteger count = new AtomicInteger();
          final Object[] values = { null, null };
  
          final CompositeDisposable set = new CompositeDisposable();
          s.onSubscribe(set);
  
          first.subscribe(new InnerObserver<T>(0, set, values, s, count));
          second.subscribe(new InnerObserver<T>(1, set, values, s, count));
      }
  
      static class InnerObserver<T> implements SingleObserver<T> {
          final int index;
          final CompositeDisposable set;
          final Object[] values;
          final SingleObserver<? super Boolean> s;
          final AtomicInteger count;
  
          InnerObserver(int index, CompositeDisposable set, Object[] values, SingleObserver<? super Boolean> s, AtomicInteger count) {
              this.index = index;
              this.set = set;
              this.values = values;
              this.s = s;
              this.count = count;
          }
          @Override
          public void onSubscribe(Disposable d) {
              set.add(d);
          }
  
          @Override
          public void onSuccess(T value) {
              values[index] = value;
  
              if (count.incrementAndGet() == 2) {
                  s.onSuccess(ObjectHelper.equals(values[0], values[1]));
              }
          }
  
          @Override
          public void onError(Throwable e) {
              for (;;) {
                  int state = count.get();
                  if (state >= 2) {
                      RxJavaCommonPlugins.onError(e);
                      return;
                  }
                  if (count.compareAndSet(state, 2)) {
                      set.dispose();
                      s.onError(e);
                      return;
                  }
              }
          }
  
      }
  
  }
  